The present technology relates to a semiconductor device that includes a plurality of electric fuses, and to a method of writing data in such a semiconductor device.
Recently, there has been proposed a semiconductor device that uses a plurality of electric fuses as storage elements. The electric fuse may be, for example, a semiconductor element having an MOS (Metal Oxide Semiconductor) structure. In such a semiconductor device, application of a necessary current to the semiconductor element may cause, for example, EM (Electro Migration) of polysilicon silicide or dissolution of polysilicon. As a result, a resistance value is varied and data is thus stored in a non-volatile manner. The above-described semiconductor device stores data by irreversibly varying element characteristics of the electric fuse. Due to such properties, data is allowed to be programmed in the above-described semiconductor device only once, and the above-described semiconductor device is therefore called an OTP (One Time Programmable) memory. The OTP memory utilizing the electric fuse is typically used assuming that data of “0” is stored in the electric fuse before EM that has low resistance, and data of “1” is stored in the electric fuse after EM that has high resistance.
A memory that utilizes the irreversibility of the element characteristics as described above is disclosed, for example, in Japanese Unexamined Patent Application Publication Nos. 2008-84454 and 2007-323786.